Pipe coupling



P 1943- L. T. H. GREIG PIPE COUPLING Original Filed Dec. 19, 1941Inventor W4 M W K}; Attorneys I V I/ o/I Patented Apr. 13, 1943 1 .rirnCOUPLING Louis Thomas Hutchison Greig, Naleing, England Originalapplication December 19, 1941, Serial No.

' 423,673, now Patent No. 2,310,073, dated February 2,1943. Divided andthis application October 15, 1942, Serial No. 462,174. In Great BritainDecember 5, 1940 3 Claims. (Cl. 284-17) This invention relates to pipecouplings and particularly to self-sealing pipe couplings comprising twoseparable hollow members mounted respectively on the terminal portionsof the pipes to be coupled and provided with valves tending .to closetheir respective pipe terminals but operating to open each other byabutment of the valves and valve seatings upon connection of thecoupling members. y

In known cou'plinzs of the above character it has been the practice toprovide an abutment seal for preventing leakage between the two.coupling parts but with such form of sealing a tight joint is noteflected until the connection of the coupling parts. is completed and,in some cases, the moment of opening of the valves is partly dependentupon the resiliency of the seal.

It is the object of the present invention to provide amethod of sealingthe coupling in which these disadvantages are overcome and which willprevent leakage from the coupling parts upon disconnection and entry ofair'to the pipe lines upon reconnection. v

- The invention. consists in the provision of a seating for one of saidvalves acting as a spigot in a socket of the opposed coupling part, aseal or packing provided in said socket adapted to close the joint uponcoupling.

Preferably, the said seal is disposed in a transverse plane extendingthrough the abutting faces of the coupling parts at the movement offirst connection. a

Reference will now be made to the accompanying drawing which illustratesa preferred embodilike openingin the member l5 whilst the throat 2c isformed by a cylindrical extension provided on the member I1 andconstituting a spigot for engagement in the socket of member IS.

The two fittings I5, II are each provided with a spring loaded valvemechanism for sealing off the terminal portions of the pipes upondisconnection of the coupling, said valve mechanisms comprising a fixedrigid valve stem 21 extending.

coaxially of the inlet fitting, which stem at its outer end carries avalve head 28. The valve head 28 is fixed, and the movable valve elementis constituted by an annular'se'ating 29 which is urged towards thevalvehead'by a compression spring .30. Interposed between thecompression spring 30 and the annular valve part 29 is a pres sure plate3| which serves to compress a packing washer 32. v

Extending axiallyof the hollow outlet fitting I1 is a valve spindle ison which a movable valve head is slidable axially, being urged by meansof a compression spring 35 towards a fixed valve seating 36. V

Referring now to the features of the present invention there is providedfor sealing the coupling against leakagev in the assembled condition aresilient sealing washer 2| located in a groove formed in the outerthroat or socket 1|9, said sealing washer having an internal diametersuch as to provide an interference fit with the cooperating inner throatmember or spigot 20, that is, the washer provides a fluid tight joint byengagement with the periphery of the spigot but allows sliding movementof the spigot relative to the washer. The washer 2| is arranged so as toextend in a transverse plane passing through the abutting faces of thecoupling parts, that is, the

hush valve faces and seatings at the moment 'of first connection of saidparts.

If desired, an abutment seal 22 may be located in a groove formed in thewall or in a stepped portions of the fitting ll adjacent the inner endof the throat 20 so'as to be squeezed between this wall and the outerend of the throat I9 when the coupling is completely assembled.

It is important to note'that when the, coupling parts are separated thevalve facesand seatings provide flush surfaces, andthus the opposedmembers can be presented to each other with virtually complete airexclusion. In addition, by the positioning of the seal or packing 2iabout the abutting faces the coupling is sealed against entry of airfrom the commencementv of the opening movements of the valves. Thus theinvention provides a construction which is particularly suitable for usewith hydraulic circuits in which the medium employed is constitutedbyliquid which needs to be kept entirely free of air.

This application is a division of application Serial No. 423,673, filedDecember 19, 1941, which has matured into PatentNo. 2,310,073, grantedFebruary 2, 1943.

I claim:

1. A self-sealing coupling comprising, a first seat, said valve seathaving a portion of reduced external diameter, a resilient packing ringoverlying said portion of reduced diameter, a follower, a spring actingonsaid follower to compress said resilient packingv ring and to urgesaid valve seat to a position closing the annular space defined by thevalve and socket, means defining a rigid annular valve seat on the endof said projection, a second valve coacting withsaid rigid valve seat,and means resiliently urging said second valve against said rigid valveseat to close oil! (the end of said projection, said defining a rigidannular valve seat on the end of said projection, a second valvecoacting' with said rigid valve seat, and means resiliently urging saidsecond valve against said rigid valve seat to close oil the end of saidprojection, said valves and said seats being in a position and of a sizeto mutually abut when the projection is inserted in the socket, wherebyupon such insertionthe rigid valve seat andvalve displace, re.-spectively, the resiliently urged valve seat and valve to open the endsof both conduits for intercommunication, while the packing ring coactswith the annular valve seat when the socket is closed and with thecylindrical surface of the projection when it is open to prevent leakagein both cases.

2. A self-sealing coupling comprising, a first conduit terminating in acylindrical socket, a second conduit terminating in a cylindricalprojection adapted for insertion in said socket, a packing rin'gcountersunk within said socket adjacent its endin a position to liebetween the cylindrical surfaces of the projection and socket when theyare engaged, a valve in said socket defining therewith an annular spaceof a diameter increasing rearwardly of the end of the valve, means forrigidly supporting said valve in the plane of said packing ring, anannular valve valves and said seats being in a position and of a sizeto, mutually abut when the projection is inserted in the socket, wherebyupon such insertion' the rigid valve seat and valve displace,respectively, the resiliently urged valve seat and valve to open theends of both conduits for intercommunication while initial movement ofthe resiliently urged annular valve seat further loads the spring tofurther compress the resilient packing ring to afford a seal during theact of engagement, the other packing ring functioning to seal the socketwhen it is closed and to seal between the socket and projection whenthey are engaged.

3. A self-sealing coupling as claimed in claim 1 in which each conduitis curved at a point rearwardly of the respective valve and in which themeans for rigidly supporting the first mentioned valve is a stemextending straight from a portion of the conduit wall beyond the bend tothe valve and in which the means resiliently urging the second valve isa telescoping valve stem extending straight from a portion of theconduit wall beyond the bend to the second valve, whereby the resultantforce of compression is transmitted along straight lines to a side wallof the conduits.

LOUIS THOMAS HUTCHISON GREIG.

